Edge welding



Patented Apr. 28, 1936 UNITED STATES PATENT CFFICE EDGE WELDING ofPennsylvania.

Application July 31,

4 Claims.

This invention relates to edge welding, and specifically to the weldingof metallic edging, or stripping used to bind the edges of anon-metallic covering material.

The object of the invention is to provide a method of, and apparatusfor, protecting the corner regions of a covering of non-metallicmaterial from -destructive heating, during the formation of a weldedjoint at the ends of strips of metallic edging material which are inabutment at a corner of the non-metallic covering material.

Attractive articles of furniture, such as sinks, desks, and kitchentables, may be made by covering a, flat body of sheet metal,constituting a splash board, or drain board, of a sink, or the top of adesk or table, with a covering sheet of suitable non-metallic material.Examples of non-metallic material suitably used as coverings of thistype, are linoleum, composition cork, rubber iiberboard, and micarta.

When such a covering of non-metallic material is applied to anunderlying base, as by being cemented thereto, it is highly desirablethat the edges of the composite structure of metallic and non-metallicmaterials, so made up, be bound by edging strips embracing the edges ofthe material of both sorts. Such binding prevents edge curling of thenon-metallic covering and produces a pleasing finished appearance of thesink, or other article of furniture.

Since a prime requisite of the structure is that it present a pleasingappearance, it is very desirable that the meeting edges of the metallicbinding strip used be welded in their regions of abutment at the cornersof the sink top, or the like, which is bound. The difficulty encounteredin so doing is that, in order to present the desired pleasingappearance, the edging must be welded along lines which lie over, oradjacent the covering layer of non-metallic material.

The covering materials which are preferred for their appearance,smoothness, and commercial availability, are subject to deteriorationunder the influence of relatively intense heat. It is diiicult,therefore, to make suitable weld between the edges of the metallicstripping, without fusing, igniting, or scorching the surface of thenon-metallic covering material at the corner regions in which themetallic edging is Welded.

In the accompanying drawing Fig. I is a fragmentary plan view, showing acorner of a composite plane element, such as a sink top, with edgebinding applied thereto in strips abutting 1934, Serial No. 737,757

at their ends, and showing a shield of my special form in position toprotect the non-metallic covering of the composite structure during awelding operation at the ends of the metallic binding strips.

Fig. II is a vertical sectional view through the composite structure,edge binding, and shield, taken on the plane of section line II-II inFig. I.

Fig. III is a similar vertical sectional view, taken on the plane ofsection line III-III in Fig. I.

In the drawing, reference numeral I designates the metallic base towhich a covering 2 of non-metallic material is attached. The coveringmaterial is shown as rabbete-d along its edge, and with a binding Strip3, of light springy metal lying with its upper flange 3a in therabbetted edge region of the covering. A foot la of the metallic base isshown as embracing a wooden form member 4; and the lower il-ange 3b ofthe edging strip embraces this foot of the metallic base, resiliently toengage the edging strip in position. As shown, upper flange 3a of theedging strip 3 is bowed upwardly, and houses in the concavity of thisbowed region a ller strip 5, having a flat under face which bears uponthe rabbeted edge region of the non-metallic covering element 2. Thisller strip 5 may be made of wood or other inilammable material, ascharring of the strip is of no moment, and it is so confined that itcannot burst into llame during the operation of welding.

It is to be understood that the showing of the drawing is exemplaryonly, insofar as concerns a specific contour of edging strip, asgenerally similar forms of edging may be welded by practising my method.Also the specic edging shown constitutes no part of my invention, but isa form of edging disclosed to me by one Eugene E. Brey.

Fig. I of the drawing shows two edging strips 3 meeting at a corner ofthe structure, and having their adjacent ends mitered to form a diagonalline of meeting 6, which is' to be the weld line between them. Inpreparation for welding, I place over the corner surface of thenon-metallic covering 2, a thin-walled Vessel 1, which is made of somesuitable metal, but which desirably is of copper because of the highheat conductivity of that metal. Copper is also suitable as a metal forthe shielding vessel 'l for the reason that it does not tend to oxidizeunder the temperature resulting from the welding operation, and doesvnot, therefore, tend to stain the linoleum, or other non-metalliccovering on which it is placed.

This metallic vessel 1, which I term a jig,

is of substantially closed structure, comprising a bottom 8, upstandingwalls S and I0, and an upper wall, or cover, II. For its use as ashield, the jig I has in its upper wall ll an opening for the receptionof a cooling medium. As shown, the upper wall II of the jig has thereina relatively restricted opening I2, which serves as a port for theintroduction of water and as a vent for the escape of vapor. If it bedesired to use a solid, such as dry ice, congealed carbon dioxide, asthe cooling medium, the port in the upper wall of the jig is desirablyof an area greater than that shown.

The two walls 9 of the jig which lie away from the edges of thestructure, in the working position of the jig shown in Fig. I, may beperpendicular to the bottom B of the jig. The walls I0, which lieadjacent the edging strips 3, are, however, desirably contoured toconform to the inwardly presented face contour of the edging strips inthe lower region of the strips adjacent the covering material 2.

As shown in Fig. II of the drawing, the lower regions Illa of the wallsIII incline upwardly and outwardly from the jig bottom 8, so that theymay closely approach the convex lower longitudinally extending regionsof the strips. Desirably, the lower regions Illa of the walls Ill areslightly concave in outer-face presentation, so that they may actuallyembrace some proportion of the edging strip face. The upper regions Illbof the walls I each inclines outwardly and downwardly to meet the lowerwall region IDa of each of the sides IU.

It will be observed from Fig. II of the drawing, that the jig 1 thusoverlies that inner belt of each upper edging strip flange 3a which liesdirectly upon the surface of covering material 2 in the edge region ofthe covering. This belt, or band, of covering material is, therefore,fully protected by the jig.

It is of course, impossible that a weld be made along the weld line 6,without fully exposing this line for the welding action. To this end thecontoured walls I0 of the jig are terminated short of a line of normalmeeting, and a forward wall I3 intervenes to interconnect their edges.As shown in Fig. III of the drawing this bridge wall I3 slopesdownwardly and outwardly, so that its lower edge I3a meets the inneredge of flange 3a at the extreme inner end of the weld line 6. It does,however, expose a minimized area of the bands or flanges, 3a which liesdirectly upon the covering material 2.

It is to be understood that the contour of jig walls I0 is exemplarygenerally of the contouring of the jig wall to conform to the inner facecontour of the edging strips. If an edging strip of contour differentfrom that shown be used, the walls I0 of the jig will naturally beappropriately contoured in conformity with the shape of that differentedging strip.

To perform an edge welding operation in accordance with my method, thejig 1, filled with water or other suitable cooling medium, is positionedas shown in the drawing. With the jig in position, the act of welding isperformed on the two adjacent strips 3 along the diagonal corner line 6.During welding, the jig protects the face of the covering 2 whichotherwise would be exposed, and also protects from heat the inner edgeof flanges 3a by which heat otherwise would be transmitted to thecovering in the region of this contact. The cooling medium prevents heatabsorbed by the upper region of the jig from so raising the temperatureof the jig bottom as to injure the covering.

Even with the protection afforded by jig 1, it is important that thewelding operation be properly conducted. In making the weld, I mayemploy an `Oxy-acetylene torch, and draw the flame from it to a veryfine tip. I employ a welding wire of small diameter, and have found wirehaving a diameter of one-sixteenth inch suit* able in conducting mymethod.

Referring to Fig. III of the drawing, in which the actual weldingoperation is illustrated, the weld is begun at the inner extremity ofweld line 6, with the flame tip I4, and the tip I5 of the welding wiredirecte-d angularly outward from the horizontal plane of theirsuspension. The weld is run rapidly, and the metal must be so rapidlyfused that the flame does not pause at any point in line 6, as it ismoved outwardly therealong.

By performing my method with the use of a closely fitting jig of heatconducting material, and comprising a cooling medium, I have been ableto weld the mitered corners of metallic binding strips without causingcharring of, or other deterioration in, a non-metal1ic covering elementwhich is susceptible to the effect of high temperature.

While the operation of welding two adjacent edging strips has been shownas performed at a corner, as such specific welding operating is the onemost difficult to perform, it is to be understood that an operation maybe performed at any region along a length of edging. This may be done bybringing the skew wall I3 up to the weld line in a length of welding. Ifdesirable, the equivalent of the bridging, or skew, wall I3 may be madein one of the side walls of the jig by indenting the wall in a regionadequate to expose the line of weld.

I claim as my invention:

1. The herein described method of making welded inter-connection betweentwo adjacent strips of metallic edging which contact at least one edgezone of a relatively flat sheet of nonmetallic material susceptible ofdeterioration under elevated temperature which comprises shield* ing anarea of the non-metallic material in the region of the junction linebetween the edging strips by positioning thereon a heat-conductingvessel with a. substantially plane bottom wall thereof overlying thesaid area of the non-metallic material and extending to the line ofcontact of the non-metallic material with the metallic edging to bothsides of the junction line between the edging strips while exposing thesaid junction line, rapidly running a Welding fiame over the junctionline between the edging strips, and in Welding protecting thenon-metallic material from the heat of welding by means of a coolingmedium lying in the vessel and in interposition between the weldingflame and the bottom wall of the vessel.

2. The herein described method of making welded inter-connection betweentwo adjacent strips of metallic edging which embrace at least one edgezone of a relatively flat sheet of nonmetallic material susceptible ofdeterioration under elevated temperature which comprises shielding anarea of the non-metallic material in the region of the junction linebetween the edging strips by positioning thereon a vessel with asubstantially plane bottom wall thereof overlying the said area of thenon-metallic material and overlying the meeting margins of thenon-metallic material and the edging strips to both sides of thejunction line between the edging strips while exposing the said junctionline, rapidly running a welding flame over the junction line between theedging strips, and in welding protecting the non-metallic material fromthe heat of welding by means of a cooling medium lying in the vessel andin interposition between the welding flame and the bottom wall of thevessel.

3. The herein described method of making welded inter-connection betweentwo adjacent strips of metallic edging which Contact at least one edgeZone of a relatively flat sheet of nonmetallic material susceptible oideterioration under elevated temperature which comprises shielding anarea of the non-metallic material in the region of the junction linebetween the edging strips by positioning thereon a heat-conductingvessel with a substantially plane bottom Wall overlying the said area ofthe non-metallic material and extending to the line of contact of thenon-metallic material with the metallic edging to both sides of thejunction line between'the edging strips, effecting a Weld at thejunction line between the edging strips, and in welding protecting thenon-metallic material from the heat of Welding by means of a static bodyof cooling medium overlying substantially the entire bottom wall of theheat-conducting vessel and the area of non-metallic material shieldedthereby.

4. The herein described method of making welded inter-connection betweentwo adjacent strips of metallic edging which embrace at least one edgezone .of a relatively flat sheet of nonmetallic material susceptible ofdeterioration under elevated temperature which comprises shielding anarea of the non-metallic material in the region of the junction linebetween the edging strips by positioning thereon a vessel with asubstantially plane bottom wall thereof overlying the said area of thenon-metallic material and overlying the meeting margins of thenon-metallic material and the edging strips to both sides of thejunction line between the edging strips while exposing the said junctionline, effecting a weld at the junction line between the edging strips,and in welding protecting the non-metallic material from the heat ofWelding by means of a static body of cooling medium loverlyingsubstantially the entire bottom wall of the heat-conducting vessel andthe area of non-metallic material shielded thereby.

WILFERD F. NEWSON.

